Plate clamp



Patented Nov. 13, 1928.

UNITED STATES` PATENT OFFICE.

LOUIS A. SCHMIDT, OF BROOKLYN, NEW YORK, ASSIGNOR T HOE & CO.,l INC., OF NEW YORK7 N. Y., A. CORPORATION 0F NEW YORK.

PLATE CLAMP.

Application led .Tune 6,

This invention relates to certain improvements in plate clamps.

In printing practice, where stereotype or similar plates are employed, the plates are clamped on the plate supports by means of clips which lap over the edges of the plates and by which the plates are clamped against suitable abutment, so that they are rigidly held in position during the printing opera- 10 tion. In printing certain products, as for instance newspapers, the printing is usually effected on rotary machines in which the plate supports are cylinders capacit-ated to carry a number of plates wide, that is, widthwise of the cylinder. Between two adjacent plat-es are formed what are usually termed margin spaces, that is, spaces in which no printing is effected, so that th-e desired margin between the pages is produced, and at times it is desirable to provide margin spaces of different widths. It also frequently happens that different width products are to be produced on the cylinder and provision must be made for adjusting the clamps accordingly, and it may often happen that a double widepage is required, so that certain of the clamps have to be removed from the cylinder. The various changes can be quickly and effectively made by the rotary clamp having` differently formed clamping surfaces, either of which upon the rotation of the clamp may be brought toward a plate on the support, such a clamp being described and claimed in my prior Patent No. 1,450,609, dated April 3, 1923.

however, that the printing plates are cast in some instances from wet mats and in other instances from ldry mats. When a wet mat is used, after the mat is pressed into the form,

it is dried ina heated press while still in contact with the form, andthere is practically no shrinkage; hence the plate cast from a wet mat is substantially the same size as the form from which the mat was made. In the use of dry mats, however, they are removed from the form immediately after the impression is made and the slight amount of moisture which they cont-ain is driven off by placing the mats in a scorcher. A slight shrinkage occurs during the scorching and the plate cast from dry mats is therefore smaller than the form. At times advantage is taken of this shrinkage and a smaller width web or sheet used when printing from dry mats. On account of the IC smaller size of the plate, however, a change in It frequently happens in printing practice, I

1927. Serial No. 196,705.

the position of the plate clamps which hold the plate on the plate support 1s necessary.

It is the especial object of the presentinvention to improvethe rotary clamp of my prior patent so that this clamp can be readily and quickly adjusted sidewise to compensate for these slight differences in the widthwise dimensions of the plates.

With this and other objects not specificallyV f referred to in view, the invention consists inv view of a part of a plate cylinder showing the improved clamp as employed with twoplates of a certain width;

Figure 2 is a similar view showing the rela# tive position of the clamp when used for clampingtwo narrower plates;

Figure 3 is a similar view showing the position of the parts when clamping a double wide plate;

Figure 4 is a detail sectional view showing the position of the clamp adj usted to compensate for slight variations in the Width of the plates of Figures 1 and 2, and

Figure 5 is a sectional end view, partly broken away, showing certain details of construction.

Referring now to these drawings, the invention has been illustrated as employed with a plate support to carry two or more plates wide, three such plates, indicated at l, 2 and- 3 in Figures 1 and 2, being shown, these plates having the usual bevelled edges 4. In the particular construction illustrated, the plate support is a cylinder, indicated at 5, but it will be undestood as to certain of its features' the invention is capacitated for use in structures in which plate supports other than cylinders are employed.

In accordance'withthe invention, there is provided an improved plate clamp which is provided with two clamping surfaces arranged on different sides of the clamp, these surfaces in the particular clamp here shown being in offset relation to'each other, and there being a plain side for use with the double wide plate shown in kFigure 3. This clamp yis so arranged that it may be manipulated to bring either the plain side or either of the plate lioldingclipsl into operative' position with reiN spect tothe surface of the cylinder and, pret; erably, this Will be effected by a rotary move-V ment, so `that-by,tur-ning thefclamp'by means:- of a suitable tool the-desired side may be brought into position, such a clamp providing means for quickly and effectively clampingI .1J

plates varying considerably in Width. The

improved clamp Will also `includemeans."`

whereby small differences in the Widths of the plates inaybe compensated `for and, prefer@y ably,this"-Will beeffected byqa rotarynuove-v ment "of" fthe clamp, so that the *adjustments rovided'with undercut sides V8 correspondzoi'ingjwftiiei beveled Sid-ee er the plate. An:

other 'side/of thisclafm1i, as 9, is provided with' a'clamp=10,'alsohaving-undercutffsi-des 11 "for enigagirigA the be'velled` -edges l lopt the plate'.

Thel clampis also `formed bna third .sidel12 with a flat or plain surface. It-Willfbel ob#` served in the particular'clainpfillustratediin the*presentfease*th'atthe sur-'faces andx 10 are inolisct relation toeach other,' thejclamp be ing* AWide enough so* thatr'thi's offsetting proj duces therequired variation mspacing of the plates,fas for instance a "colufmn Width.l=

`Where bothv ltheplates, las o'r insta-nce, the

plates 1 and 2 in'fFiguref"1,"or 'the' plates 13,

llofiFiure 2 are of thesame-Width, the road"tationfoi'the clamp properly positions the clamping surfaces with respect to the edges of the -plates`."- there the plates are'of slightly diferentwvidth, however,"due to theuse oi drymatlbr a Wetmat inffmaling 4.thenf1, the-- 40 clamping surfaceswvould-'not be inproper lposition for clamping the edges of the plate. Mea1is-,*there"fore,are providedby "the present invention, as before stated, whereby"theA clamp 'may lbel given f a vsidevvi'se rmovementV -to com-pensate' for this difference in l 'the 1 plate45 Widths and-,iur 'the best constructions', f this #is effected byfjarrotarymovement 'of the clampf itself-fi l p Y wWhile they particular construction for mounting' the t'clamp inthe l'cyl'ir'ide'r -so` thatv this may tbe fe'lect'ed may be somewhat varied,

in 'fth'eparticular construction illustrated the cylinder isi rec'essedto `receive Aa clamp carry` I ing-case orfboX 15 inwhichis rigidly support#` ed a stud 16 having' a threaded-end 171' The" threaded cindfol this' stud is'threadedinto the clamp,r und the1 'clampcarrying` casel orfboX'is,"

aslshow'iumfade ,somewhatflongier than the clamp. It' Willfbe observed that by `rotating 50 the' fclamp 'one' :'turn'f the clamp Will' be Xgiven a 'side'ivise movement in the box andthe clampv Wil'lf beAk moved i the idistanc'ef corresponding" Ito one1'thread, :asi for instance f the diferencebef tween the/position shown ini'liieures 1 ande.I 55" Thus the clafmp'ing'surfacefll of Figures 1 and 4 is inclampingrrelation with thewplatesbut has been moved sidewise a slight Adistance so as to compensate for the slight di'tlerence 1n the VWidth of thcaplates.-

Theroutside plates 1 and 13 are clampedl in the usual manner by means otclamping,`

f blocls18 operated by the usual Vscrew rod 19, und the inside edge of the inner plates may be claniped'against a clamp 22, Which if desired may be movable, being'mounted on a screwrod-28 operated by 'a gear: 24;' I lde-v sired, a spring pin 20, seeFigure,fmaybezw providedv for holding thezclampfi-n`adjusted position, this pin takingint'o a hole 21 Vformed@` inthe Walls'of the box or case y15.V A

With theconstructionn shown-"andi def-'y scribed,'-it will be seen that the clamps'fm'ayr be `readily.adjusted forfclampingplatesafof widths -varyingl fa certain predeterminedfdisfg tance,as a column, and= at lthe same` time mayf'e be adjusted :for clamping-such'platesfzwhere the-plates vary' slightlyunwidth: Y

While theinvention haswbe'en shown'candff described lin its i preferred'i'form'pit'iwill .abe understood that certainrvariationsvniayx be-fmf mad'ein the formio thefclampingi:surfaces u and` in the arrangement fo'thefclamping sursf faces' on' the clamp :and-*in otherxdetails shown'- and describedwithout Vdepart-ingr froinfthe-inf-f vention las delined'in the appended'fclaimsw-t 954Q 1. In'a plate clamp,"` the `combination-rot `a f plate' supportga recesszwin'rtheff support, .a f rotary 'clamp-in thev recessihaving:diiierentlyn formedfaces; either of vvhichm'ay be brought 10.9 toward-a plate ontleVV support by yrotating,the 1 clamp, and f means A`for: effecting'- a esideivisef movement' of the clamp inthe recessfto fads: justit for slightdilerences in rfthe"fWid-th of=l a plate. Y l

2. In a plate" clamp, A'thef conibinationor-a plate support, a recess in/the support, a rotary clamp yin the rec'ess'lhaving fdiff'rently it'orined.` faces, either ot which maybebroughtitowardi aplate on Y-the. supportby rotatingfthefclamp, 111.0 and means Wherebythes rotation of the1clamp= effects a sideWise-movementthereoffto adju-st thev clamp 'fort slight. dii'erences in fthevwijdth? of a plate.'I Y

3. In a fplatecla'rnp;thecombinationuoti ar 115 plate support', a recess-in the; support, :a :rotary` clamp inf ther; recess l' having f5.' diferenttyj formed faces, either :ofwhichfmaytbe brought; towardr a plate onthe supportby 'rotatingfthe clamp, aV recess' in the support; a box'ini the: 120 recess longer than the* fclamp, and -zineans whereby the fclamp may 'be given fside-Wise-I m'oveine'ntin' the recess by rits rotation@y y l1.' `In a plate clamp,=,^the "combinationfof plate support; a recess inthe supporta:rotarfy 125 clamp? in the recess, yandl means-whereby the: rotationfof `the fcla'm-p' effects :a rsideWise-:ad-1l justingvm'ovement thereof." e

5. In a plateclamp the'.combinationf` ofwa plate support, a recessinthesupportyla rotary 130 clamp in the recess, and a fixed threaded pivot on which the clamp is threaded.y

6. In a plate clamp, the combination of a plate support, a recess in the support, a rotary clamp shorter than the recess mounted therein, and a xed threaded pivot in the recess on which the clamp is threaded.

7. In a plate clamp, the combination of a plate support, a recess in the support, a box 1n therecess, a clamp block shorter than the 10 box mounted therein, and a threaded rod fixed a ainst rotation in the box on which the clamp lock is threaded.

In testimony whereof, I have hereunto set my hand.

LOUIS A. SCHMIDT. 

